Problem: Some frogs were dancing on a log. $7$ frogs jumped into the pond. There were $2$ frogs left on the log. How many frogs were dancing on the log in the beginning?
Answer: We can use subtraction to find the missing whole: $\Box - 7 = 2$ We can also add all of the frogs together: $7 + 2 = {\Box}$ $9$ frogs